(a) Field of the Invention
The invention relates to a method for removing resilient gallery lining frames in mining and tunnelling, consisting of a number of mutually overlapping lining section segments which have a box-like profile, preferably leaving free a longitudinal gap, and which are inserted into one another in a dissimilar manner by their overlapping ends and are optionally braced with respect to one another by a wedge system acting on a slot of the inner section, whereby any ties present are first removed, for example by loosening their nuts or by bending, and the section segments are then released from one another in order to recover the respective lining frames.
The gallery lining serves in mining and tunnelling for making safe and keeping open the galleries or corresponding chambers. The resilient gallery lining reacts as soon as a load exceeds the prescribed insertion resistance of the segments, which is set up and maintained in the overlapping end regions. Because of this the lining yields. No dangerous deformation of the gallery lining frame takes place along the prescribed insertion path. The cost of a resilient gallery lining frame makes removal, that is recovery, of the gallery lining worth while when the gallery has served its purpose. As a rule, the gallery lining which has been removed is straightened and then used again.
(B) Description of the Prior Art
Resilient gallery lining frames consisting of so-called hollow sections inserted one in another are known. During the removal of such lining frames, the nuts of the ties, which hold together the adjacent segments in the overlaps and are necessary to brace them, are loosened. As a result of this, the cohesion of the ends of the segments is immediately lost. Consequently, the lining frames can be recovered directly after removal of the ties.
A disadvantage, however, is that because of the insertion of the segments, repeated, i.e. intervening, tightening of the nuts and because of rust, loosening the ties using spanners or similar tools is only rarely possible. In the few cases in which nuts can be loosened from ties, the use of spanners is ruled out because of the dangerous nature of this work, which results from loss of the cohesion of the ends of the segments. It is, therefore, customary to loosen the nuts from a distance with expressly developed devices, for example to blow them off, and to remove the lining in so far as it is still standing. This method is, however, not applicable to the gallery lining frames described at the beginning and not pertaining to the state of the art. For such a resilient gallery lining, because of its segment ends inserted one into another in a dissimilar manner, has the characteristic that, even after the loosening of any ties present, the lining section segments hold together and the gallery lining frame remains standing.
The invention is therefore aimed at making it possible to remove without danger a gallery lining as described at the beginning of this specification, having sections inserted one into another in a dissimilar manner, and thus to effect recovery of the lining.